Ok, so a lot of us are amateur photographers, but there's really no need to look like a complete amateur when we pick up and point our SLR or DSLR to get a shot. Holding your SLR properly, while not making it totally obvious that you are not a pro, also has a lot of advantages. Here's what you need to know.
For starters, holding a camera at both sides of the body like the picture below is usually a dead give away that you don't know what you are doing.
The problem with this grip is that you haven't really got maximum control of the movement of your equipment and so problems such as blurred photos due to shaking are going to crop up. The slower your shutter speed, the more pronounced these negative effects are going to be.
Secondly, you don't have instant access to the capabilities of your SLR or DSLR because you have to remove your left hand to use the controls on your lens. This is not a great state of affairs.
Now, while you will have a hard time eliminating camera shake altogether with solwer shots while you are hand-holding your camera, there are a few things you can do to minimise the problem and most of the time, it won't be any problem whatsoever.
The widely-regarded best way to hold your SLR is to grip the lens with your left hand and use your right hand for the body controls (which are primarily positioned on most SLRs to be most accessible using this grip).
Here is the correct way to hold your SLR:
And here is a great little Youtube demonstration: